In the process of manufacturing a thin-film transistor liquid crystal display (TFT-LCD), vacuum cell-assembly is a core process in forming a cell. Vacuum cell-assembly refers to a process that: an array substrate (TFT) and a color filter (CF) substrate of a TFT-LCD are respectively adsorbed by an upper machine table and a lower machine table in a nearly vacuum environment, and adhered to each other after the upper machine table and the lower machine table move in opposite directions. The substrate adsorbed by the upper machine table can be referred to as an upper substrate, and the substrate adsorbed by the lower machine table may be referred to as a lower substrate. In the process of manufacturing another display, e.g., e-paper, an upper substrate and a lower substrate also must be subjected to vacuum cell-assembly.
With the development of the production line of LCD panels, the dimension of an LCD panel become larger and larger, and the requirements on the accuracy of the force applied to an upper substrate and the mode of separating the upper substrate become higher and higher as well. Currently, widely applied devices for adsorbing and separating the upper substrate mainly comprise silicon foam rubber chuck (SFC) devices and plate silicone rubber chuck (PSC) devices.
As illustrated in FIG. 1, in an SFC device, an upper machine table 1 is provided with a plurality of circular SFC cohesive modules 2 which are configured to adsorb a substrate; when the substrate is separated from the cohesive modules 2, a computer controls the upper machine table 1 to move up and meanwhile controls air chambers 3 in the middle of the SEC cohesive modules 2 to be aerated and bulged so as to separate the substrate. In general, the number of the SFC cohesive modules 2 is more than 200. As illustrated in FIG. 2, in a PSC device, an upper machine table 1 is provided with large-area PSC cohesive modules 4 which are configured to adsorb an upper substrate; a pin 5 is disposed between the PSC cohesive modules 4 and the upper machine table 1; and when the substrate is separated from the cohesive modules 4, a computer controls the upper machine table 1 to move up and meanwhile controls the pin 5 to project down so as to separate the substrate. In general, the number of the PSC cohesive modules 4 is four.
However, because both the SFC device and the PSC device cannot sense the force applied to the upper substrate and the flatness of the upper substrate, the force applied to the upper substrate may be uneven in the process of applying pressure force to form the cell, and hence the upper substrate may be crushed or the cohesive state between the upper substrate and the lower substrate can be poor after the process of applying pressure force to form the cell, and consequently the cell-assembly accuracy and the cell-assembly quality can be affected.